Battery shut off switch

[SmartWillie]

I don't tow yet... Still have to sell the cruising sailboat to buy the motorhome. I have noticed that on my 2008 smart, when you put the transmission in Neutral and switch off the key, the Transmission indicator lamp that shows "N" still glows hours after turning the key off. So there is a little current flow. I think that when I do start to tow the smart I will wire the RV power to the smart to keep the battery charged while towing.

I have left the smart for several months while sailing and have come home to a dead battery. So there is a drain on the battery from the radio, computers and doo-waw-dittys...

I did take "Shorty" in for the 2009 transmission update and got a new battery and owners guide that does say that you need a battery disconnect switch while towing. If I were to put one in, it wouldn't be under the floorboard next to the battery.

Willie

[rcexplorer]

Last week, took my Smart 09 to the Bedford Ohio service department, the reason, my ABS light came on and stays on. The service manager explained that the front wheels/breaks got really hot. Said it must be my RV breaking system. I do not have a kill switch. Put shifter in N, the turn key off. Also needed to use a bungy cord for tracking. I had to add a 24/7 power (Cig lighter) so my break box, that sits on the floor with an arm attached to the break peddle. So, here's what I am trying to figure out, is my break to sensitive, or as someone wrote that the breaks lock up at +25mph?? The dealer is ordering a new sensor and they will cover under warranty. Car has less then 850 miles. HELP!

[fortow]

Originally Posted by SmartWillie

I don't tow yet... Still have to sell the cruising sailboat to buy the motorhome. I have noticed that on my 2008 smart, when you put the transmission in Neutral and switch off the key, the Transmission indicator lamp that shows "N" still glows hours after turning the key off. So there is a little current flow. I think that when I do start to tow the smart I will wire the RV power to the smart to keep the battery charged while towing.

I have left the smart for several months while sailing and have come home to a dead battery. So there is a drain on the battery from the radio, computers and doo-waw-dittys...

I did take "Shorty" in for the 2009 transmission update and got a new battery and owners guide that does say that you need a battery disconnect switch while towing. If I were to put one in, it wouldn't be under the floorboard next to the battery.

Willie

The "N" continues to be lighted for a short time but does go out. There is always 'dark' current draw on a car's battery but it is minimal. If you leave a battery connected for months without disconnecting it will drain. This has nothing to do with towing a car though.

[fortow]

Originally Posted by rcexplorer

Last week, took my Smart 09 to the Bedford Ohio service department, the reason, my ABS light came on and stays on. The service manager explained that the front wheels/breaks got really hot. Said it must be my RV breaking system. I do not have a kill switch. Put shifter in N, the turn key off. Also needed to use a bungy cord for tracking. I had to add a 24/7 power (Cig lighter) so my break box, that sits on the floor with an arm attached to the break peddle. So, here's what I am trying to figure out, is my break to sensitive, or as someone wrote that the breaks lock up at +25mph?? The dealer is ordering a new sensor and they will cover under warranty. Car has less then 850 miles. HELP!

I think are some assumptions being made here. The fact that your ABS system failed had nothing to do with towing unless there was actually overheating taking place and that was the cause of the ABS failure. You may have set the tow brake system up so that the brakes were activated at a too high a level or the sensitivity was set too high. It could also be that the tow brake box was improperly positioned so that there was some pressure on the brake peddle all the time causing some brake drag which led to the overheating.

If you want to find out if the brakes lock up at 25 mph with the transmission in neutral and the key in the off position then pick an untravelled road, put the transmission in "N" at a speed higher than 25 and turn off the key. My bet is that nothing will happen. The brakes on my car remain cool after towing for hours.

[rcexplorer]

Originally Posted by fortow

I think are some assumptions being made here. The fact that your ABS system failed had nothing to do with towing unless there was actually overheating taking place and that was the cause of the ABS failure. You may have set the tow brake system up so that the brakes were activated at a too high a level or the sensitivity was set too high. It could also be that the tow brake box was improperly positioned so that there was some pressure on the brake peddle all the time causing some brake drag which led to the overheating.

If you want to find out if the brakes lock up at 25 mph with the transmission in neutral and the key in the off position then pick an untravelled road, put the transmission in "N" at a speed higher than 25 and turn off the key. My bet is that nothing will happen. The brakes on my car remain cool after towing for hours.

The service manager said that he had never seen a break as over heated as mine. I will now investigate more into the "Even Break Tow System" and settings.
Much thanks

[donschweika]

At first I did not use a battery cut off switch. Somehow the ignation switch got turned on during installation of brake buddy. During a turn the front wheel squealed. I believe the stability controll may have been kicking in. Since battery cut off switch, I no longer worry about the ignation switch accidently getty turned on.

[fortow]

Originally Posted by donschweika

At first I did not use a battery cut off switch. Somehow the ignation switch got turned on during installation of brake buddy. During a turn the front wheel squealed. I believe the stability controll may have been kicking in. Since battery cut off switch, I no longer worry about the ignation switch accidently getty turned on.

Tell me something - if you disconnect the battery, how do you know the transmission is in the neutral position? Can't the lever easily be nudged accidentally to D just as the ignition key can inadvertently be turned to 'on'?

Personally, I'd never disconnect the battery for that reason. I do put the lever in the 'N' position then turn the key off and watch for the dash display to go off, and for a second verification check the 'N' light as well which takes a little longer to go out. After that, no one goes back into the car before towing.
Disconnecting the battery is the factory's idea of circumventing the inevitable ignorance and even occasional stupidity of the driving public.

There is another problem that you could encounter that has nothing to do with the battery - the 'E' brake (parking brake) could be applied and not noticed that it was. That did happen to me once (stupidity? ) but fortunately I was starting off from a gravel road and another motorhome owner waved at me to stop because he saw the locked wheel. No harm done but it could have been bad. Just a heads-up.

[b2fortwo]

So how many use auxiliary brakes on their Smart Cars while towing? It seems with such a light weight this doesn't seem necessary. It's not only under 3000 lbs, but it's under 2000 lbs. Most of the States laws say brakes needed for anything over 3000 lbs.

As long as you're well under the GCWR the motorhome's brakes are more then ample to stop.

[HerrZ]

brakes break me up!

[fortow]

Originally Posted by b2fortwo

So how many use auxiliary brakes on their Smart Cars while towing? It seems with such a light weight this doesn't seem necessary. It's not only under 3000 lbs, but it's under 2000 lbs. Most of the States laws say brakes needed for anything over 3000 lbs.

As long as you're well under the GCWR the motorhome's brakes are more then ample to stop.

The problem is that there are places that require a braking system for the towed vehicle and most areas also require a breakaway braking device. The 1800 lbs itself added to the GVWR really is not the issue.